import os
arr = os.listdir()
print(arr)


n = 3 #the number of line to be read and deleted

for i in range(len(arr)):
    print(i)
    print(arr[i])
    file = open(arr[i], 'r')
    file_name = str(arr[i]) + '0'
    print(file_name)
    file_new= open(file_name, 'a')
    Lines = file.readlines()
    count = 0
    for line in Lines:
        count = count+ 1
        if (count>3):
            file_new.write(line)
    file_new.close()